Ratchet-drill brace



(No Model.)

W. P. NOLAN. RATGHBT DRILL BRAGB.

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UNITED l STATES PATENT OFFICE.

WILLIAM P. NOLAN, OF SAN FRANCISCO, lCALIFORNIA.

RATCHETfDRILL BRACE.

SPECIFICATION forming part of Letters Patent No. 506,931, dated October17, 1893.

Application filed December l5, 1892. Serial No. 455.323. (No model.)

which the speed of the tool shaft can be conveniently changed from ahigh rate of speed to a single motion corresponding to the movement ofthe crank arm or vice versa.

The invention consists of certain parts and details, and combinations ofthe same, as will be hereinafter described and then pointed out in theclaims.

Reference is to be had to the accompanying, drawings forming a part ofthis specitioatioml in which similar letters of reference indicatecorresponding parts in all the figures.

Figure 1 is a side elevation of the improve! Fig. 2 is an enlargedsectional elevament. l tion of part of the improvement. Fig. 3 is asectional plan view of the same on the line 3--3 of Fig. 2. Fig. 4 is aninverted sectional plan view of the same on the line 4-4 of Fig.

v2; and Fig. 5 is an inverted sectional plan view of the same on theline 5-5 of Fig. 2.

The improved ratchet drill brace is provided with a frame A preferablymade U- shaped and formed at its upper end with a handle B and at itslower end with a hollow casing or disk C formed with an internal gearwheel C and a hub C2 for the tool shaft, as hereinafter more fullydescribed.

From the handle B projects a bearing B engaging one end of the crank armD arranged to turn within the frame A and formed at its lower end withan enlargement D formed with a bearing D2 arranged in alignment with thehub O2 of the disk O. The

bearing D2 is engaged by the hub E of a ratchet wheel E formed at itslower end with a flange E2 carrying a number of gear wheels F havingtheir shafts arranged with their centers in a circle, as plainly shownin Fig. 3, so that the said gear wheels are in mesh with the internalgear wheel C of the casing or disk C. The gear wheels F also engage acentral gear wheel G formed with an upwardlyprojecting shaft G looselyengaging the hub E of the ratchet wheel E, as plainly shown in Fig. 2.On the top of this central gear wheel G are arranged ratchet teeth G2adapt ed to engage corresponding ratchet teeth E3 formed in the hollowratchet wheel E, as plainly shown in Figs. 2 and 4.

From the under side of the gear wheel G extends centrally, the toolshaft G3 mounted to rotate in the hub O2 projecting from the under sideof the casing O, as previously mentioned. On this tool shaft G2 areformed two annular grooves G4 and G5 adapted to be engaged by the forkedend H of a slide H mounted to slide on the under side of the casing O,as plainly illustrated in Figs. 2 and 5. The forked end H of the slidepasses through an opening in the hub O2, so as to either engage thegroove G4 or G5 in the tool shaft G3 to hold the latter in the desiredposition. When the forked end H of the Vslide H engages the groove G4then the central gear wheel G is in mesh with the gear wheels F, butwhen the slide His pulled outward so that its forked end H disengagesthe groove G4 and the tool shaft G3 is moved upward, then the forked endH engages the annular groove G5, thus holding the tool shaft G3 in anuppermost position. In this case, the gear wheel G slides upward withthe tool shaft and consequently moves out of mesh with the gear wheels Fand into mesh by its ratchet teeth G2, withl the ratchet teeth Es of theratchet wheel E.

The slide H is formed with a longitudinally-extending slot H2 throughwhich passes the screw I screwing in the under side of the disk C and inthis slot H2 is held a spring J, one end of which is attached on thescrew I and the other end presses onto the inner end of the slide, so asto hold the latter in contact with its forked end H with the respectivegroove G4 or G5. The ratchet wheel E is adapted to be engaged by eitherof two pawls K or K pivoted on the under side of the enlargement Dof thecrank arm D; see Figs. 2V and 4. The pawls K and K are pressed on by acoiled spring K2, so as to hold the free ends of the pawls in engagementwith the ex- IOO terior teeth of the ratchet wheel E. In order to throweither of the pawls K or K out of mesh with the ratchet Wheel E, a leverL is provided similar to the one shown and described in the abovementioned patent, so that further description of this part of themechanism is not deemed necessary.

The tool shaft G3 carries a chuck N of any approved construction. New,it will be seen that when the several parts are in the positionillustrated in Fig. 2, and the crank arm D is turned, then a rotarymotion is given to the ratchet wheel E by the said crank arm o onaccount of the connection of the latter by the respective pawl K or Kthrough the ratchet Wheel E. Therotary motion of the latter istransmitted by the gear wheels F rolling o the internal gear Wheel C tothe cent-ral gear wheel G, so that the tool shaft G3 is rotated at avery high rate of speed. Now, when it is desired to rotate the toolshaft G3 at a low rate of speed correspondingr to that of the motion ofthe crank arm D, then the operator first withdraws the slide H from thegroove G4 and then pushes the tool shaft G3 upward t-o permit the slideI-I to engage the other groove G5. The upward movement of the tool shaftG3 disconnects the gear wheel G from the gear wheels F, as previouslymentioned but at the same time moves the ratchet teeth G2 in mesh withthe ratchet teeth E3 of the ratchet wheel E. The rotary motion of thelatter is now directly transmitted to the tool shaft G3, so that thelatter rotates with the motion of the crank arm D.

Having thus fully described my invention, I claim as new and desire tosecure by Letters Patentl. In a ratchet drill brace, the combination`Wheel, and a tool shaft mounted to slide and carrying a gear wheelhaving ratchet teeth adapted to engage correspond ing ratchet teethformed in the said ratchet Wheel/the said gear wheel being also adaptedtov mesh into the said series of gear wheels, substantially as shown anddescribed.

2. In a ratchet drill brace, the combination with a frame formed with acasing having an internal gear wheel, of a crank arm mounted to turnwithin the said frame, a ratchet Wheel adapted to be locked to the saidcrank arm, a series of gear Wheels held on the said ratchet Wheel and inmesh with the said internal gear wheel, a tool shaft modnted to slideand carrying a gear wheel having ratchet teeth adapted toengageeorresponding ratchet teeth formed in the said ratchet wheel, thesaid gear wheel being also adapted to mesh into the said series of gearwheels, and a spring pressed slide held on the said casing and adaptedto engage annular grooves in the said tool shaft, substantially as shownand described.

3. In a ratchet drill brace, the combination with a frame formed withacasing having an internal gear wheel, of a crank arm mounted to turnwithin the said frame,a ratchet wheel adapted to be locked to the saidcrank arm, aseries of gear wheels held on the said ratchet wheel and inmesh with the said internal gear Wheeha tool shaft mounted to slide andcarrying a gear wheel having ratchet teeth adapted to engagecorresponding ratchet teeth formed in the said ratchet wheel, the saidgear wheel being also adapted to mesh into the said series of gearwheels, and a pawl and lever mechanism for locking the said crank arm tothe said ratchet wheel, substantially as shown and described.

WILLIAM P. NOLAN.

